Molecular Biology Commons^™

Characterization Of Endothelial Nitric Oxide Synthase Serine-600 Phosphorylation, Kevin Patel

Master of Science in Chemical Sciences Theses

Endothelial nitric oxide synthase (eNOS) is part of a family of three nitric oxide synthase (NOS) enzymes that catalyze the production of nitric oxide (NO). NO is a gaseous, free-radical signaling molecule that has a variety of cellular and physiological functions that range from maintaining cardiovascular homeostasis to neurotransmission. The function of NO greatly depends on the concentration and is cell type specific. eNOS is the most regulated of the three NOS isoforms and the mechanisms of regulation can be through protein-protein interactions and posttranslational modifications. A connection with eNOS and the cell cycle has begun to form with recent …

Functional Characterization Of The Ovarian Tumor Domain Deubiquitinating Enzyme 6b, Jasmin M. D'Andrea

USF Tampa Graduate Theses and Dissertations

The posttranslational modification ubiquitination is major regulatory mechanism used throughout cell signaling pathways such as cell cycle regulation and the DNA damage response. As such, the E3 ligases and their deubiquitinating enzyme counterparts, which conjugate and deconjugate ubiquitin to and from protein substrates respectively, must be tightly regulated to prevent aberrant cellular behaviors that could lead to diseases such as cancer.

Of the five families of deubiquitinating enzymes, the Ovarian Tumor Domain (OTU) family is fairly unique and under-studied; many of its family members hold a linkage specificity to certain ubiquitin chains and a number of them have been implicated …

The Role And Regulation Of Alternative Polyadenylation In The Dna Damage Response, Michael R. Murphy

Dissertations, Theses, and Capstone Projects

Cellular homeostasis is achieved by the dynamic flux in gene expression. Post-transcriptional regulation of coding and non-coding RNA offers a fast method of adapting to a changing cellular environment, including deadenylation, microRNA (miRNA) pathway, and alternative polyadenylation (APA). In this dissertation, I explored some of the mechanisms involved in the post-transcriptional regulation of gene expression. The main hypothesis in these studies is that a single APA event after DNA damage is governed by specific conditions and factors outside of current known regulators of APA, and that the resultant transcript has a role in the DNA damage response (DDR). My aims …

Regulation Of Alteration/Deficiency In Activation 3 (Ada3) By Acetylation And Its Role In Cell Cycle Regulation And Oncogenesis, Shashank Srivastava

Theses & Dissertations

The ADA3 (Alteration/Deficiency in Activation 3) protein is a transcriptional adaptor protein that was initially discovered as a component of several HAT (Histone Acetyltransferase) complexes, the enzyme complex responsible for histone acetylation, which is a prerequisite for transcription. Earlier the studies from Dr. Band’s laboratory and that of others’ have deciphered a crucial role of ADA3 in cell cycle regulation (both through G₁/S and G₂/M phase transitions) and in maintaining the genomic stability.

While our laboratory investigated the mechanism behind the role of ADA3 in G₁/S transition, the same remained unknown for G_{2 …}

Dephosphorylation Of Iqg1 By Cdc14 Temporally Regulates Actin Ring Formation, Daniel Patrick Miller

Masters Theses

"Cytokinesis is the final step in cell division when the cell separates the cytoplasm by contracting a ring composed of filamentous actin (F-actin) and type II myosin. Iqg1, an IQGAP family member, is an essential scaffolding protein in budding yeast (S. cerevisiae) required for actin recruitment to, and contraction of, the actomyosin ring. Actin is recruited by the calponin homology domain (CHD) in anaphase after Iqg1 is localized to the bud neck. Consensus sites for the cyclin-dependent kinase (CDK) Cdc28 were identified flanking the CHD. This led us to the hypothesis that phosphorylation of Iqg1 by Cdc28 negatively regulates actin …

Regulation And Action Of Skp2 And Rhoa In Cell And Tumor Models: Investigation Into The Molecular Mechanisms Responsible For The Aggressive Phenotype Of Triplenegative Breast Cancer, Katrina D. Fagan-Solis

Open Access Dissertations

Breast cancer tops the list of new cancer cases and is predicted to be the second leading cause of cancer deaths in women in 2012. The primary objective of the present study was to provide insights into the molecular mechanisms underlying the aggressive growth and metastasis of triple-negative and basal-like breast cancers. To study increased growth and invasive behavior in triple-negative and basal-like breast cancers we utilize both an interesting and relevant cell culture model and examination of human tissue.

In this study, we use the Tamoxifen-selected, MCF-7 derivative, TMX2-28 breast cancer cell line. TMX2-28 cells are triple-negative in that …

Artemis Interacts With The Cul4a Ubiquitin E3 Ligase Complex And Regulates The Cell Cycle Progression, Yiyi Yan

Dissertations & Theses (Open Access)

Artemis, a member of the SNM1 gene family, is one of the six known components of the non-homologous end joining pathway. It is a multifunctional phospho-protein that has been shown to be modified by the phosphatidylinositol 3-kinases (PIKs) DNA-PKcs, ATM and ATR in response to a variety of cellular stresses. Artemis has important roles in V(D)J recombination, DNA double strand breaks repair and damage-induced cell-cycle checkpoint regulation. The detailed mechanism by which Artemis mediates its functions in these cellular pathways needs to be further elucidated. My work presented here demonstrates a new function for Artemis in cell cycle regulation as …